Touch panel

ABSTRACT

A touch panel having high durability is provided. Either one or both of a display device and a flexible panel have island-shaped protective bodies formed on surfaces of electrode layers (upper electrode layer, lower electrode layer), and a transparent conductive film is exposed between the protective bodies. Since the protective bodies protrude highly from the surface of the transparent conductive film, when the flexible panel is pressed and the upper electrode and the lower electrode layer are brought into contact, a load to be applied to the transparent conductive film is reduced by the protective bodies, so that the transparent conductive film is not broken.

This application is a division of U.S. application Ser. No. 12/814,039,filed Jun. 11, 2010 now U.S. Pat. No. 8,031,183, which application is acontinuation application of International Application No.PCT/JP2008/072033, filed Dec. 4, 2008, which claims priority to JapanPatent Application No. 2007-323491, filed Dec. 14, 2007. The entiredisclosures of the prior applications are herein incorporated byreference in their entireties.

BACKGROUND OF INVENTION

The present invention generally relates to a technical field of touchpanels.

Touch panels have been widely used in an ATM, a vending machine, ahandheld terminal, a handheld game device, an electronic guide displayplate, a car navigation, a cell phone, or the like.

The touch panel is generally formed by bonding two panels together, onthe surfaces of which transparent electrode films (such as, an ITO thinfilm) is formed with these transparent electrode films facing eachother. At least one of the two panels has flexibility; and when theflexible panel is pressed, the transparent electrode films are broughtinto conduction at a pressed location. Such a touch panel includes theso-called matrix touch panel and the so-called resistive touch panel.

In either of the touch panels, the transparent electrode films arebrought into conduction by being directly or indirectly contacted toeach other, so that when the same location is repeatedly pressed, thetransparent electrode film may be clouded or cracked due to thefriction. There is a need to address this problem particularly with thetransparent electrode of a panel on the side pressed by the flexiblepanel. See JP-A 2000-081952.

SUMMARY OF THE INVENTION

The present invention provides a highly durable touch panel.

The present invention is directed to a touch panel in which first andsecond panels have first and second substrates and first and secondtransparent electrodes respectively disposed on the corresponding firstand second substrates, the first and second panels being separatelyarranged in a state such that faces having the first and secondtransparent electrodes disposed thereon are facing toward each other,and the first and second transparent electrodes are brought into contactwhen either one or both of the first and second panels are pressed,wherein the first transparent electrode comprises a transparentconductive film and protective bodies which are formed in a piled-upfashion on a surface of the transparent conductive film and scattered inthe form of islands on the surface of the transparent conductive film,wherein a protecting film containing either one or both of a nitride ofa metallic material and an oxide of the metallic material is exposed onsurfaces of the protective bodies.

The present invention is directed to the touch panel, wherein themetallic material comprises any one or more kinds of metals selectedfrom a metal group consisting of Ti, Nb, Zr, Ta and Si, and thetransparent conductive film has a lower resistance than the protectingfilm.

The present invention is directed to a method for producing a touchpanel, which includes forming a first transparent electrode on a surfaceof a first substrate to prepare a first panel, and bonding together thefirst panel and a second panel having a second transparent electrodeformed on a surface of a second substrate such that the first and secondtransparent electrodes are facing toward each other, wherein the firsttransparent electrode forming step comprises forming a transparentconductive film composed mainly of a transparent oxide on a surface ofthe first substrate, forming plural metallic flocculated bodies on asurface of the transparent conductive film by depositing any one or morekinds of metals selected from a metal group consisting of Ti, Nb, Zr, Taand Si, and forming a protecting film by performing either one or bothof an oxidation reaction to oxidize the metallic flocculated bodies anda nitriding reaction to nitride the metallic flocculated bodies.

The present invention is directed to the method for producing the touchpanel, wherein a step for forming the metallic flocculated bodies and astep for forming the protecting film are alternatively and repeatedlycarried out.

The present invention is constructed as described above. Since theprotective bodies highly protrude from the transparent conductive film,when the first and second transparent electrodes are to be brought intocontact, the second transparent electrode contacts the protective bodiesfirst, and then contacts the transparent conductive film. Since a loadto be applied to the transparent conductive film is reduced by theprotective bodies, the transparent conductive film is less likely to beabraded.

In the case where the protective bodies and the transparent conductivefilm are made of the same material, the protective bodies are planarizedevery time the transparent electrode is repeatedly pressed, so that thesurface of the transparent electrode finally becomes flat, and theabrasion resistance decreases.

In the present invention, the transparent conductive film is made of thetransparent oxide such as ITO or AZO and at least surface portions ofthe protective bodies (the protecting film) are constituted by the oxideand/or the nitride different from the transparent oxide constituting thetransparent conductive film, so that the mechanical strength of theprotective bodies is higher than that of the transparent conductivefilm. Thus, even when the protective bodies are repeatedly pressed, thesurface of the first transparent electrode does not become flat, and thetransparent conductive film is protected.

A part of the protective bodies may be made of a metal alone. However,since the metal alone has a weaker mechanical strength when comparedwith an oxide or a nitride of that metal, it is desirable to have atleast the surfaces of the protective bodies constituted by the metaloxide and/or the metal nitride.

EFFECTS OF THE INVENTION

Since the first transparent electrode has not only excellenttransparency but also high abrasion resistance, it is not cracked orclouded even when being repeatedly pressed, so that the lifetime of thetouch panel is prolonged. Further, while a film of the protective bodiesis formed, a surface of a metal target is not oxidized or nitrided andthe sputtering speed does not decrease, so that the film-forming speedof the protective bodies is high. Furthermore, since the substrate doesnot reach a high temperature, a highly flexible plastic substrate can beused.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view for illustrating a touch panel of a firstembodiment.

FIG. 2 is a sectional view for illustrating a film forming apparatus tobe used in the present invention.

FIG. 3 is a sectional view for illustrating a touch panel of a secondembodiment.

FIG. 4 is a schematically sectional view for illustrating a slidingtester.

FIG. 5 is a SEM photograph of Comparative Example 1.

FIG. 6 is a SEM photograph of Comparative Example 2.

FIG. 7 is a SEM photograph of Example 1.

FIG. 8 is a SEM photograph of Example 2.

FIG. 9 is a SEM photograph of Example 3.

FIG. 10 is a SEM photograph of Example 4.

FIG. 11 is a SEM photograph of Example 5.

FIG. 12 is a SEM photograph of Example 6.

FIG. 13 is an SEM photograph of Example 9.

FIG. 14 is a SEM photograph of Example 11.

FIG. 15 gives SEM photographs of Comparative Example 1, Examples 1 and1a, and Examples 6, 6a and 6b.

FIG. 16 is a SEM photograph of Example 13.

FIG. 17 is a SEM photograph of Example 14.

FIG. 18 is a SEM photograph of Example 15.

DETAILED DESCRIPTION OF THE INVENTION

Reference numeral 1 of FIG. 1 represents an example of a touch panel;and the touch panel 1 includes a display device 10 (first panel) and aflexible panel 20 (second panel).

The display device 10 includes a plate-like display panel 19 such as anLCD (liquid crystal display) device or a PDP (plasma display panel).Either one of a front surface and a rear surface of the display panel 19is used as a display surface 24 so that image information (such as,graphics or letters) may be displayed on the display surface 24.

Here, the display device 10 includes, in addition to the display panel19, a transparent substrate 11 (first substrate) disposed on the displaysurface 24, an antireflection layer 15 disposed on a surface of thesubstrate 11, and a lower electrode layer 30 (first transparentelectrode) disposed on a surface of the antireflection layer 15.However, it may be that the substrate 11 is constituted by a part of thedisplay panel 19 and the display surface 24 is constituted by a surfaceon a side of the substrate 11 upon which the antireflection layer 15 islaminated. Further, the lower electrode layer 30 may be formed directlyon the surface of the substrate 11 without providing the antireflectionlayer 15.

A plurality of spacers 29 is disposed at an interval on a surface of thelower electrode layer 30.

The flexible panel 20 includes a flexible film 21 (second substrate)such as a resin film, and an upper electrode layer 27 (secondtransparent electrode) formed on a surface of the flexible film 21. Theflexible panel 20 is mounted on the spacers 29 in a state such that thesurface having the upper electrode layer 27 formed thereon is facingtoward the lower electrode layer 30. Therefore, the upper electrodelayer 27 and the lower electrode layer 30 are spaced apart by the heightof the spacer 29.

Each of the flexible film 21, the upper electrode layer 27, the lowerelectrode layer 30, the antireflection layer 15 and the substrate 11 istransparent, so that image information displayed on the display surface24 can be observed from the flexible panel 20 side.

The antireflection layer 15 is constituted by laminating plural layers(here, three layers) of transparent films 12 to 14 each having adifferent refractive index.

When an outside light, such as sunlight or an illumination light, whichpasses the flexible panel 20 and is reflected at a surface of the lowerelectrode layer 30, is taken as a surface reflected light, therefractive index and the film thickness of each of the transparent films12 to 14 are designed so that phases of interface reflection lightsreflected on the respective surfaces of the transparent films 12 to 14are deviated from the surface reflected light; and thus, the surfacereflected light may be attenuated by the interface reflection lights.Therefore, an image displayed on the display panel 19 of the presentinvention can be clearly observed.

The quality of the material and the film thickness of the upperelectrode layer 27 allow upper electrode layer 27 to be deformabletogether with the flexible film 21. When the flexible panel 20 isdepressed and the flexible film 21 is bent, the upper electrode layer 27is deformed together with the flexible film 21, so that the entireflexible panel 20 can be deformed.

A user of the touch panel 1 observes the image information of thedisplay panel 19, selects a position based on that image information,and presses the flexible panel 20 at the selected position. The pressedposition of the flexible panel 20 is curved, and the upper electrodelayer 27 approaches the lower electrode layer 30 at the pressedposition.

The lower electrode layer 30 includes a transparent electrode film 31disposed on a surface of the substrate 11, and protective bodies 32scattered on a surface of the transparent electrode film 31. Because theprotective bodies 32 are piled up on the surface of the transparentconductive film 31 in the form of an island, when the upper electrodelayer 27 approaches the lower electrode layer 30 due to pressing, thesurface of the upper electrode layer 27 is in contact with theprotective bodies 32.

The surface of the transparent conductive film 31 is exposed between theprotective bodies 32. The thickness of the protective body 32 is assmall as less than 2.5 nm (target value when the film is formed), andthe size (diameter) of the planar shape of the protective body 32 is assmall as 30 Å or more to 1000 Å or less (3 nm or more to 100 nm orless), so that the upper electrode layer 27 is in contact with thesurface of the transparent conductive film 31 exposed between theprotective bodies 32 due to pressing.

At least a surface portion (protecting film) of the protective body 32is composed mainly of either one or both of an oxide of a metallicmaterial of Ti and/or Nb and a nitride of the metallic material thereof.That is, the protecting film is composed mainly of one or more kinds ofreaction products selected from the group consisting of an Nb oxide, aTi oxide, an Nb nitride and a Ti nitride.

The transparent conductive film 31 is composed mainly of a materialhaving a resistance lower than the main component of the above-mentionedprotecting film, such as ITO or AZO. When the upper electrode layer 27comes into contact with the surface of the transparent conductive film31, the upper electrode layer 27 and the lower electrode layer 30 areelectrically connected.

The upper electrode layer 27 and the lower electrode layer 30 arerespectively connected to an analyzer. When the touch panel 1 utilizesthe resistance film system, the pressed position is known from a voltagevalue of a magnitude corresponding to a pressed position. When the touchpanel 1 utilizes the matrix system, the pressed position is known fromthe position of a wiring electrically conducting due to pressing.

The surface portion of the protective body 32 has a mechanical strengthhigher than that of the transparent conductive film 31, and theprotective body 32 is not damaged even when the first transparentelectrode 30 is repeatedly pressed. In addition, since the protectivebody 32 protrudes highly from the surface of the transparent conductivefilm 31, when the first transparent electrode 30 is pressed, a load tobe applied to the transparent conductive film 31 is reduced by theprotective bodies 32. Therefore, the transparent conductive film 31 isnot damaged much; and thus, the first transparent electrode 30 is notclouded or cracked.

Next, a film forming apparatus to be used for producing the first panelwill be explained. Reference numeral 50 in FIG. 2 shows one embodimentof the film forming apparatus.

This film forming apparatus 50 includes a vacuum chamber 51, a rotaryshaft 53, a metal target 61, an inorganic target 62, a transparentconductive material target 63 and an ion gun 55.

The rotary shaft 53 is arranged inside the vacuum chamber 51, and arotary body 52 is fixed around the rotary shaft 53. The rotary shaft 53is connected to a non-illustrated rotating means. When a power istransmitted from the rotating means, the rotary shaft 53 rotates arounda central axis (rotary axis) passing through the center of the rotaryshaft 53, and the rotary body 52 rotates around the same rotary axistogether with the rotary shaft 53 inside the vacuum chamber 51.

A holding device not shown is provided at a side face of the rotary body52. Substrates to be held are held at the holding device. The substratesto be held are fixed to the rotary body 52 in a state such thatfilm-forming surfaces are facing toward a side opposite to the rotaryaxis and set in parallel to the rotary axis. When the rotary shaft 53rotates, the substrates to be held rotate around the rotary axis alltogether with the rotary body 52.

An ion gun 55 is disposed such that at least a portion thereof providedwith a discharge opening 69 is located inside the vacuum chamber 51 in astate such that the discharge opening 69 is facing toward the side faceof the rotary body 52.

A sputtering gas introduction system 59 is connected to the vacuumchamber 51, and a rare gas is introduced into the ion gun 55 from thesputtering gas introduction system 59 or another introduction system.The ion gun 55 plasmatizes the introduced rare gas, and the plasmatizedrare gas is taken out through the discharge opening 69 and dischargedtoward the side face of the rotary body 52 as an ion beam.

The metal target 61, the inorganic target 62 and the transparentconductive material target 63 are respectively disposed in the samevacuum chamber 51 as the vacuum chamber 51 in which the dischargeopening 69 is located, at locations which are outside a circumference inwhich the substrate to be held rotationally moves and which are alongthat circumference.

The heights of the discharge opening 69, the metal target 61, theinorganic target 62 and the transparent conductive material target 63are almost equal to a height at which the substrates to be held are heldby the holding device. When the substrates to be held move rotationally,they pass a position facing toward the discharge opening 69, a positionfacing toward the metal target 61, a position facing toward theinorganic target 62 and a position facing toward the transparentconductive material target 63.

The sputtering gas introduction system 59 is designed so as to feed asputtering gas into a space between each of the targets 61 to 63 and theside face of the rotary body 52. Power sources 66 to 68 are connected tothe respective targets 61 to 63.

A vacuum evacuation system 57 is connected to the vacuum chamber 51, thevacuum chamber 51 is evacuated to vacuum by the vacuum evacuation system57, and voltages are applied to the targets 61 to 63 from power sources66 to 68 in a state such that the vacuum chamber 51 is set at a groundpotential, while the sputtering gas (Ar, Kr or the like) is beingintroduced from the sputtering gas introduction system 59. Consequently,the targets 61 to 63 are sputtered, and particles (sputtered particles)of constituent materials of the targets 61 to 63 are discharged towardthe side face of the rotary body 52.

Thus, when the substrates to be held pass the positions facing towardthe targets 61 to 63, the particles of the constituent material of eachof the targets 61 to 63 reach surfaces of the substrates to be held.

A reactive gas feeding system 58 is attached to the vacuum chamber 51 sothat the reactive gas may be fed into a space between the dischargeopening 69 and the side face of the rotary body 52.

When the ion beam is discharged through the discharge opening 69 withthe reactive gas being fed, the reactive gas is plasmatized. When thesubstrate to be held passes the position facing toward the dischargeopening 69, it is exposed to the plasma of the reactive gas.

In the case where the targets 61 to 63 are sputtered and the rotary body52 is rotated with the reactive gas being plasmatized, when thesubstrate to be held passes the positions facing toward the targets 61to 63, the sputtered particles reach the surface of the substrate to beheld and atomic layers are formed on the surface of the substrate to beheld; and when the substrate to be held passes the position facingtoward the discharge opening 69, the plasmatized reactive gas and theatomic layer react and a layer of a reaction product can be formed.

This method is known as “metal mode”; the reactive gas is fed directlybetween the discharge opening 69 and the rotary body 52, and the atomiclayer can be reacted with the reactive gas without feeding a largeamount of the reactive gas into the vacuum chamber 51.

Therefore, even if the reactive gas can be reacted with the targets 61to 63, the partial pressure of the reactive gas within the vacuumchamber 51 can be suppressed to such a low level that the reactionproduct between the reactive gas and the targets may not be formed onthe surfaces of the targets 61 to 63.

If a background pressure level in the vacuum chamber 51 isunsatisfactory, the reaction product of the reactive gas, such as anitride or an oxide, may be formed on the surfaces of the targets 61 to63 even in the metal mode.

In order to help prevent the formation of the reaction product on thesurfaces of the targets 61 to 63, a reducing gas (reducing agent) is fedfrom reducing gas introduction systems 81 to 83 into the vacuumatmosphere (inside the vacuum chamber 51) in which the targets 61 to 63are placed.

The surfaces of the targets 61 to 63 are exposed to the reducing gas,and the targets 61 to 63 are sputtered in the vacuum atmospherecontaining the reducing gas.

Even if the plasma of the reactive gas turns around the vicinity of thetargets 61 to 63, no reaction product is formed on the surfaces of thetargets 61 to 63 because the plasma is reduced through a reaction withthe reducing gas.

Either one or both of a hydrogen gas (H₂) and a gas containing ahydrogen atom in a chemical structure can be used as the reducing gas.As the gas containing the hydrogen atom in the chemical structure,methane (CH₄), an ethane gas (C₂H₆) and the like are recited, forexample.

A gas (a rare gas, for example) to be fed into the ion gun 55 is thesame gas as the above-described sputtering gas or a gas which does notreact with the constituent material of each of the targets 61 to 63.

In this way, the surfaces of the targets 61 to 63 do not react with anyof the gases, so that the sputtering speed does not drop due to theformation of the reaction product with the reactive gas on the surfacesof the targets as in another reactive sputtering method.

Next, steps of producing the first panel by using this film formingapparatus 50 will be explained.

The inside of the vacuum chamber 51 is evacuated to vacuum by the vacuumevacuation system 57; a vacuum atmosphere is formed at a predeterminedpressure; one or more substrates 11 (first substrates) as substrates tobe held are carried into the vacuum chamber 51, while the vacuumatmosphere is being kept; and each of the substrates 11 is held by theholding device and attached to the rotary body 52.

While the vacuum chamber 51 is continuously evacuated to vacuum and therotary body 52 is being rotated, the inorganic target 62 (Si target, forexample) is sputtered, and the reactive gas (O₂, for example) isplasmatized.

When the substrate 11 passes the position facing toward the inorganictarget 62, the sputtered particles discharged from the inorganic target62 reach the surface thereof and an atomic layer (Si layer) is formed;when the substrate passes the position facing toward the dischargeopening 69, the atomic layer reacts with the plasmatized reactive gasand a transparent film 12 made of a transparent insulating material(SiO₂) is formed.

If the rotary body 52 is rotated while the sputtering of the inorganictarget 62 and the plasmatization of the reactive gas are continuing, theformation of the atomic layer and the reaction with the reactive gas arerepeatedly performed, so that the film thickness of the transparent film12 becomes greater and the surface of the substrate 11 is covered withthe transparent film 12.

When a first layer which is the transparent film 12 reaches apredetermined film thickness, the sputtering of the inorganic target 62is stopped, and another inorganic target (the metal target 61, here) issputtered while the rotation of rotary body 52 and the plasmatization ofthe reactive gas are continuing. A second layer which is a transparentfilm 13 (NbO film, here) having a different refractive index from thatof the first layer is formed in such a manner that the entire surface ofthe first layer which is the transparent film 12 is covered with thetransparent film 13.

When the second layer which is the transparent film 13 reaches apredetermined film thickness, the sputtering is stopped, a third layerwhich is a transparent film 14 (SiO₂ film, here) having a refractiveindex different from that of the second layer is formed by sputteringthe inorganic target 62, different from the target 61 used in theforming of the second layer, in such a manner that the surface of thesecond layer which is the transparent film 13 is covered with thetransparent film 14, thereby forming an antireflective layer 15.

In this connection, so long as the transparent films 12 to 14 eachhaving the different refractive indexes are laminated for theantireflective layer 15, the kinds and the order of the targets to besputtered and the number of the transparent films 12 to 14 are notparticularly limited.

After the antireflective film 15 is formed, the plasmatization of thereactive gas and the sputtering of the inorganic target 62 are stopped,the transparent conductive material target 63 is sputtered while theintroduction of the sputtering gas and the rotation of the rotary body52 are continuing, and a transparent conductive film 31 made of thetransparent conductive material is formed in such a manner that thesurface of the antireflective layer 15 is covered with the transparentconductive film 31. In this case, when the transparent conductive film31 is to be formed, oxygen is introduced into the vacuum chamber 51, ifnecessary, so as to compensate for oxygen loss.

When the transparent conductive film 31 grows to a predetermined filmthickness, the sputtering of the transparent conductive material target63 is stopped.

While the vacuum chamber 51 is continuously evacuated to vacuum, thereactive gas (oxidizing gas and/or nitriding gas) is fed to such a levelthat a product caused by the reactive gas may not be formed on thesurface of the metal target 61, the reactive gas is plasmatized, and therotary body 52 is rotated with the metal target 61 containing either oneor both of Ti and Nb being sputtered.

Since no reaction product is produced on the surface of the metal target61, metal particles (Ti and/or Nb) are discharged from the metal target61 as the sputtering particles, and when the substrate 11 passes theposition facing toward the metal target 61, the metal particles reachthe surface of the transparent conductive film 31.

Since the metal which is not oxidized or nitrided has a high cohesiveproperty, the metal particles flocculate and are piled up on thetransparent conductive film 31, thereby forming a metal atomic layer(metal flocculated bodies).

The rotating speed of the rotary body 52, that is, the moving speed ofthe substrate 11, is so high that the entire surface of the transparentconductive film 31 is not covered with the metal atomic layer, and themetal atomic layers are formed in a scattered fashion when the substrate11 once passes the position facing toward the metal target 61.Therefore, the transparent conductive film 31 is exposed between themetal atomic layers.

When the substrate 11 passes the position facing toward the dischargeopening 69, the metal atoms constituting the metal atomic layer reactwith the plasmatized reactive gas.

Since the metal atomic layer is constituted by several metal atoms whichare piled upon one another, when the substrate 11 once passes theposition facing toward the discharge opening 69, all the metal atomsconstituting the metal atomic layer react with the reactive gas, wherebya protective body 32 made of the reaction product is formed.

Note that the reaction product is a metal nitride in the case of thereactive gas being a nitriding gas, a metal oxide in the case of thereactive gas being a oxidizing gas, and a mixture of the metal oxide andthe metal nitride in the case of the reactive gas being a mixture of thenitriding gas and the oxidizing gas.

While the sputtering of the metal target 61 and the plasmatization ofthe reactive gas continue, the rotary body 52 is continuously rotated,and the formation of the metal atomic layer and the production of thereaction product are alternatively and repeatedly performed, so that thefilm thickness and the plane shape of each of the productive bodies 32become larger.

When the diameter of the plane shape of the protective body 32 grows to30 Å or more to 1000 Å or less, the sputtering of the metal target 61and the plasmatization of the reactive gas are stopped before the entiresurface of the transparent conductive film 31 is covered with theprotective bodies 32. At this time, the film formation is terminated.

The substrate 11 having the protective bodies 32 formed is carried outof the vacuum chamber 51, and attached to a display surface 24 of thedisplay panel 19. After the spacers 29 are disposed on the surface ofthe lower electrode layer 30, a touch panel 1 as shown in FIG. 1 can beobtained by bonding the display device 10 to the flexible panel 20.

When the film formation is performed in a state such that the substrateis kept still relative to the target and the ion gun as in anothertechnology, the substrate is heated to a high temperature. Consequently,the substrates have been limited to heat-resistant ones such as theglass substrates.

Since the substrate 11 is not kept still relative to the targets 61 to63 and the ion gun 55 in the above-described metal mode, the substrate11 is not heated to a high temperature, so that a plastic substrate suchas a resin film can be also used as the substrate 11, in addition to theglass substrate. Thus, the substrate 11 does not have to be a glasssubstrate.

A flexible film 21 is used as the substrate to be held, and a flexiblepanel 40 may be produced by forming a first transparent electrode (upperelectrode layer 45) having a transparent conductive film 41 andprotective bodies 42 on a surface of the flexible film 21 in theabove-described steps.

A display device 10 having a second transparent electrode (lowerelectrode layer 49) made of a transparent conductive film is prepared,and the display device 10 and the flexible panel 40 are bonded togethervia spacers 29 in the state that the upper electrode layer 45 is facingtoward the lower electrode layer 49, whereby a touch panel 4 as shown inFIG. 3 can be obtained.

When the flexible panel 40 of the touch panel 4 is pressed, theprotective bodies 42 are in contact with the lower electrode layer 49first, and then the transparent conductive film 41 exposed between theprotective bodies 42 is in contact with the lower electrode layer 49.Since a larger load is applied to the protective bodies 42 than thetransparent conductive film 41, the transparent conductive film 41 isless likely to be broken.

The above explanation has been made of the case in which either one ofthe flexible panel and the display device is taken as a first panel, andthe protective bodies 32, 42 are provided on either one of the upperelectrode layer and the lower electrode layer (first and secondtransparent electrodes), but the present invention is not limitedthereto. It may be that both of the upper electrode layer and the lowerelectrode layer, that is, both of the first and second transparentelectrodes are constituted by the transparent electrode films and theprotective bodies, and the transparent conductive films and theprotective bodies are exposed in both the first and second transparentelectrodes.

Although the film thickness of the protective bodies 32 is notparticularly limited, if the protective bodies 32 grow too much, notonly the film thickness but also the plane shapes become greater, sothat the adjacent protective bodies 32 are integrated and thetransparent conductive film 31 is covered with the protective bodies.Thus, the film forming time is desirably shortened so that the filmthickness of the protective bodies 32 may be less than 2.5 nm (a targetvalue when the film is formed).

In order that the first and second transparent electrodes may be sure tobe conductive, the plane shapes of the protective bodies 32 aredesirably set to 30 Å or more and 1000 Å or less (3 nm or more to 100 nmor less) in diameter.

In the above, the case in which the entire protective bodies 32 are madeof the metal oxide and/or the metal nitride has been explained, but theinvention is not limited thereto. For example, the atomic layer can beformed thicker, and when it is exposed to the plasma of the reactive gasin a manner so that only a surface portion of that atomic layer may beoxidized and/or nitrided, the protective bodies having protecting filmof the metal oxide and/or the metal nitride formed on the surfaceportion of the metal atomic layer can be obtained.

The formation of the atomic layer and the oxidizing and/or nitriding maybe performed in different vacuum chambers or in the same vacuum chamber.For example, after the atomic layer is formed by sputtering the metaltarget 61 inside the film forming apparatus 50 of FIG. 2 withoutplasmatizing the reactive gas, the sputtering of the metal target 61 canbe stopped and the oxidation and/or the nitriding can be carried out byplasmatizing the reactive gas.

The formation of the protective bodies 32 is not limited to thesputtering method. For example, a metal atomic layer can be formed inthe vacuum atmosphere by generating a vapor of a metallic material madeof either one or both of Ti and Nb and bringing the vapor into a surfaceof the transparent conductive film 31 on the substrate 11.

Then, when the metal atomic layer is exposed to the plasmatized reactivegas (nitriding gas and/or oxidizing gas), the metal nitride and/or themetal oxide is generated on at least the surface portion of the metalatomic layer, and thus, the protective bodies 32 are formed.

Further, it may be that a raw material liquid, in which a materialconstituting the protective bodies 32 (the metal oxide or the metalnitride) is dispersed in a solvent, is poured into a tank of an ink jetprinter; the raw material liquid is discharged onto a surface of thetransparent conductive film 31 through a nozzle of the ink jet printer;liquid drops scattered on the surface of the transparent conductive film31 are formed; excess solvent is removed through drying; and theprotective bodies 32 are formed.

The metals used for the protective bodies 32 are not limited to Ti orNb. For example, a metal atomic layer may be formed by sputtering ametal target containing at least one kind of metals selected from thegroup consisting of Nb, Ti, Mg, Zr, V, Ta, Cr, Mo, W, Fe, Ni, Pd, Pt,Cu, Ag, Au, Zn, Al, In, C, Si and Sn.

In this case, at least a surface portion of the protecting film containseither one or both of at least one kind of an oxide of the metallicmaterials selected from the group consisting of Nb, Ti, Mg, Zr, V, Ta,Cr, Mo, W, Fe, Ni, Pd, Pt, Cu, Ag, Au, Zn, Al, In, C, Si and Sn and anitride of the above metallic materials.

Among the above-mentioned metals, Nb, Ti, Zr, Ta and Si are particularlydesirable from the viewpoint of the transparency, the mechanicalstrength or the like of the reaction product.

Any of the metal oxides, the metal nitrides and mixtures thereof hashigh transparency, but the metal nitrides are inclined to be coloredyellowish as compared with the metal oxides. Therefore, at least thesurface portions of the protective bodies are desirably composed mainlyof the metal oxide. More concretely, the metal oxides include titaniumoxides (TiO, TiO₂, Ti₂O₃, Ti₂O₅, etc.), niobium oxides (Nb₂O₅, etc.),tantalum oxides (Ta₂O₅, etc.), zirconium oxides (ZrO₂, etc.), andsilicon oxides (SiO₂, Si₂O₃, Si₃O₄, etc.).

The transparent conductive film 31 is not particularly limited, and forexample, it may be made of a transparent oxide composed mainly of In₂O₃and containing 0.1 atom % or more to 20 atom % or less of at least onekind of element selected from an element group consisting of the 2Agroup, the 4A group, the 2B group and the 4B group, a transparent oxidecomposed mainly of ZnO and containing 0.1 atom % or more to 20 atom % orless of at least one kind of element selected from an element groupconsisting of the 1A group, the 3A group, the 4A group and the 1B group,the 3B group and the 4B group, or a transparent oxide composed mainly ofSnO₂ and containing 0.1 atom % or more to 20 atom % or less of at leastone kind of element selected from an element group consisting of the 3Agroup, the 3B group, the 5A group and the 5B group.

As the reactive gas, either one or both of an oxidizing gas containingan oxygen atom in a chemical structure and a nitriding gas containing anitrogen atom in a chemical structure can be used. As the oxidizing gas,O₂, O₃, H₂O and the like can be used, and as the nitriding gas, N₂, NH₃and the like can be used. One kind of these reactive gases may be usedalone, or a mixed gas of two or more kinds may be used.

The antireflective layer 15 is not limited to the case where it isprovided in the display device 10. The antireflective layer 15 may beprovided between the upper electrode layer 27 of the flexible panel 20and the flexible film 21. In addition, the lower electrode layer 30 maybe provided directly on the substrate 11 (or the display surface 24)without the antireflective layer 15 being provided on the display device10. The antireflective layers 15 may be provided in both of the displaydevice 10 and the flexible panel 20.

The present invention is not limited to the case where the protectivebodies 32 and the transparent conductive film 31 are exposed on thesurface of the first transparent electrode 30. For example, the surfaceof the first transparent electrode 30 may be covered with othertransparent film such as ITO or SiO₂.

When the temperature of the substrate 11 is too low, flocculation of themetal is less likely to occur, so that the temperature of the substrate11, at the time a film of the protective bodies 32 is formed, isdesirably 80° C. or higher. Furthermore, there is a concern that thesubstrate may be deformed when the substrate is a plastic substrate andthe temperature is too high. Thus, temperature of the substrate 11 isdesirably 100° C. or less when forming the film of the protective bodies32.

EXAMPLES

Substrates 11 were attached to the rotary body 52 of the film formingapparatus 50 of FIG. 2; an oxygen gas was used as a reactive gas; and afilm of SiO₂ (Si_(x)O_(y), x and y are actual numbers), a film of Nb₂O₅(Nb_(x)O_(y), x and y are actual numbers) and a film of SiO₂O_(y), x andy are actual numbers) were laminated in the above-described steps in thedescribed order by using a metal target 61 made of Nb and an inorganictarget 62 of Si, thereby forming an antireflection layer 15.

Then, while an optimum amount of oxygen for supplementing an oxygen lossis being introduced into the vacuum chamber 51, a transparent conductivefilm 31 was formed on a surface of the antireflective layer 15 bysputtering a transparent conductive material target 63 made of ITO(In₂O₃ as a main component with SnO₂ added in 10% by weight) or AZO (ZnOas a main component with Al₂O₃ added in 2% by weight), which is used asan object to be processed.

Test pieces in the below-mentioned Examples 1 to 10 and ComparativeExamples 1 and 2 were prepared by using the objects to be processed inwhich the transparent conductive film 31 was made of ITO, among theabove objects to be processed, the below-mentioned Examples 11 and 12and Comparative Example 3 were prepared by using the objects to beprocessed in which the transparent conductive film 31 was made of theAZO.

Example 1

The object to be processed was taken out from the film forming apparatus50, and carried into a vacuum chamber of the sputtering apparatus. Ametal target 61 made of Nb was arranged in the vacuum chamber, and theobject to be processed was faced toward the metal target 61. The vacuumchamber was evacuated to vacuum, and an island-shaped thin film of theNb oxide (Nb_(x)O_(y)) was formed as protective bodies 32 by sputteringthe metal target 61, while both a reactive gas (oxygen gas) and asputtering gas were being fed into a space between the metal target 61and the object to be processed (Reactive sputtering). The film thicknessof the Nb_(x)O_(y) thin film was calculated to be 0.5 nm based on thefilm forming time.

Example 2

The rotary body 52 was rotated in the state that the object to beprocessed was attached to the rotary body 52 of the film formingapparatus 50; the metal target 61 made of Nb was sputtered; the reactivegas of the oxygen gas was plasmatized; and an island-shaped Nb_(x)O_(y)thin film was formed as protective bodies 32 by the above-mentionedmetal mode. The film thickness of the Nb_(x)O_(y) thin film wascalculated to be 0.5 nm based on the film forming time.

Example 3

The object to be processed was taken out from the film forming apparatus50, and carried into the vacuum chamber of the sputtering apparatus.While the vacuum chamber was being evacuated to vacuum, an atomic layer(Nb atomic layer) was formed in a scattered fashion on a surface of thetransparent conductive film 31 by introducing an Ar gas as a sputteringgas into the vacuum chamber and sputtering the metal target 61 made ofNb inside the vacuum chamber.

Next, while the reactive gas of the oxygen gas was being introduced intothe vacuum chamber, protective bodies 32 made of the Nb atomic layer anda Nb_(x)O_(y) protecting film covering the Nb atomic layer were formedby irradiating an ion beam toward the object to be processed from theion gun. The film thickness of the protective body was calculated to be0.5 nm based on the film forming time.

Example 4

An object to be processed was taken out from the film forming apparatus50, and carried into vacuum chamber of the sputtering apparatus. Whileonly the sputtering gas was being introduced into the vacuum chamberwithout introducing the reactive gas, an atomic layer (Nb atomic layer)was formed in a scattered fashion on a surface of the transparentconductive film 31 by sputtering the metal target 61.

Protective bodies 32 made of the Nb atomic layer and a Nb_(x)O_(y) filmwere formed by forming an Nb_(x)O_(y) thin film on the surface of theobject to be processed in which the atomic layer has been formed underthe same condition as in Example 1. The film thicknesses of the Nbatomic layer and the Nb_(x)O_(y) thin film were respectively calculatedto be 0.5 nm based on the film forming time.

Example 5

After protective bodies 32 were formed on a surface of the object to beprocessed under the same condition as in Example 4, an ITO thin film wasformed on the protective bodies 32 by sputtering a transparentconductive material target 63 made of ITO inside the vacuum chamber,while the sputtering gas and the reactive gas (O₂) were being introducedinto the vacuum chamber of the sputtering apparatus. Film thicknesses ofthe Nb atomic layer, the Nb_(x)O_(y) thin film and the ITO thin filmwere respectively calculated to be 0.5 nm based on the film formingtimes.

Example 6

Protective bodies 32 made of a thin film of a Ti oxide (Ti_(x)O_(y), xand y being actual numbers) were formed under the same condition as inExample 3 except that the metal target 61 was replaced by a target madeof Ti. The film thickness of the Ti_(x)O_(y) thin film was calculated tobe 0.5 nm based on the film forming time.

Example 7

Protective bodies 32 made of a Ti atomic layer and a Ti_(x)O_(y)protecting film were formed under the same condition as in Example 4except that the metal target 61 was replaced by a target made of Ti. Thefilm thickness of the Ti atomic layer and the Ti_(x)O_(y) protectingfilm were respectively calculated to be 0.5 nm based on the film formingtime.

Example 8

A Ti atomic layer and a protecting film of a Ti nitride (Ti_(x)N_(y), xand y being actual numbers) were formed as protective bodies 32 underthe same condition as in the above-described Example 7 except that thereactive gas was replaced by a nitrogen (N₂) gas. The film thicknessesof the Ti atomic layer and the Ti_(x)N_(y) protecting film wererespectively calculated to be 0.5 nm based on the film forming time.

Example 9

A Ti atomic layer and a protecting film of a mixture of a Ti oxide and aTi nitride (Ti_(x)O_(y)N_(z), x, y and z being actual numbers) wereformed as protective bodies 32 under the same condition as in theabove-described Example 7 except that the reactive gas was replaced by amixed gas of the nitrogen (N₂) gas and the oxygen gas (O₂). The filmthicknesses of the Ti atomic layer and the protecting film ofTi_(x)O_(y)N_(z) were respectively calculated to be 0.5 nm based on thefilm forming time.

Example 10

Protective bodies 32 were formed under the same condition as in Example7. A target made of Si was preliminarily placed inside the vacuumchamber of the sputtering apparatus, and a thin film of Si_(x)O_(y) (xand y being actual numbers) was formed by sputtering the target, whilethe sputtering gas and the oxygen gas were being introduced into a spacebetween the target and the object to be processed. The film thickness ofthe Si_(x)O_(y) thin film was calculated to be 0.5 nm based on the filmforming time.

Example 11

Protective bodies 32 were formed under the same condition as in theabove-described Example 4 except that an object to be processed having atransparent conductive film 31 made of an AZO thin film was used.

Example 12

Protective bodies 32 were formed under the same condition as in theabove-described Example 7 except that an object to be processed having atransparent conductive film 31 made of an AZO thin film was used.

Comparative Example 1

An object to be processed having a transparent conductive film 31 madeof ITO was taken as a test piece without modification.

Comparative Example 2

While a target made of Nb was being sputtered without the introductionof the oxygen gas or the discharge of the ion beam, the rotary body 52,to which the object to be processed was attached, was rotated, and theprotective bodies 32 of a Nb atomic layer were formed in island shapes.The film thickness of the Nb atomic layer was calculated to be 0.5 nmbased on the film forming time.

Comparative Example 3

An object to be processed having a transparent conductive film 31 madeof an AZO thin film was used as a test piece without modification.

Since the film thickness of 0.5 nm is too thin, it is difficult tophysically measure the film thickness. Therefore, a thick film enablingthe film thickness to be measured was formed, and the relationshipbetween the film thickness and the film forming time was preliminarilydetermined. Based on this relationship, a film forming time necessaryfor forming the thin film of 0.5 nm was determined, and the thickness(target value) of a film formed during the film forming time was takenas 0.5 nm.

<Observation of Surface States>

Surfaces of test pieces of Comparative Examples 1, 2, Examples 1 to 6,Example 9 and Example 11 were photographed at a magnification of 100,000with a scanning-type electron microscope (SEM). The SEM photographs ofComparative Examples 1, 2, Examples 1 to 6, Example 9 and Example 11 areshown in FIGS. 5 to 14, respectively.

Referring to FIG. 5, it is found that the surface of the transparentconductive film 31 is kept flat when no protective bodies 32 are formed.

Referring to FIG. 6, the Nb atomic layer is formed in a scatteredfashion and piled up in the form of islands. It is found that the metalatoms, which are not oxidized or nitrided, are likely to be flocculated.

As compared with FIG. 6 and FIG. 8 to FIG. 14, FIG. 7 shows that therewere fewer island-shaped protective bodies 32. The protective bodies 32in Example 1 are a film formed by the reactive sputtering. Since thereactive gas is fed between the target and the substrate 11 in thereactive sputtering, the surface of the target is oxidized or nitrided,and the metal oxide or the metal nitride reaches on the substrate 11.Accordingly, it is presumed that no flocculation occurred.

On the other hand, referring to FIG. 8, the protective bodies 32 areformed in a scattered fashion and piled up in the form of the islands.In Example 2, since the step of forming the metal atomic layer and thestep of reacting the metal atomic layer with the reactive gas arerepeatedly carried out (metal mode), it is presumed that theflocculation occurs when the metal atomic layer is formed.

In FIGS. 9 to 14 as well, it is confirmed that protective bodies 32 arealso piled up in the form of islands, and, irrespective of the filmforming method and the kinds of the metal and the reactive gas, theflocculation occurs, if the metal atomic layer is once formed.

That is, it is seen that the island-shaped protective bodies 32 areformed, if the metal atomic layer is reacted with the plasmatizedreactive gas or when a layer of a reaction product between the metal andthe reactive gas is formed on the metal atomic layer by the reactivesputtering, after the metal atomic layer is formed on the surface of thetransparent conductive film 31.

Meanwhile, the protective bodies 32 are piled up in the form of islandsin FIG. 14, and it was confirmed that the island-shaped protectivebodies 32 are formed according to the film forming method of the presentinvention, irrespective of the kind of the transparent conductive film31.

Sliding characteristics tests shown below were carried out by using thetest pieces in the above-described Examples 1 to 12 and ComparativeExamples 1 to 3.

<Sliding Characteristics Tests>

Reference numeral 90 of FIG. 4 shows a sliding tester. The slidingtester 90 has a base 91; ball bearings 96 are arranged on the base 91;and a stage 98 is placed on the ball bearings 96.

A test panel was prepared by bonding each test piece to the flexiblepanel 20 of FIG. 1 together with a double-faced adhesive tape such thatthe surface on which the protective bodies 32 were formed was facingtoward the upper electrode layer 27.

Each test panel was placed on the stage 98 with the face on a side ofthe flexible panel 20 facing upward, and an oscillator tip portion 95made of a resin was attached to a lower end of an oscillator 94 abovethe stage 98.

Further, a load 93 was attached to an upper end of the oscillator 94 sothat the total amount of the oscillator 94, the oscillator tip portion95 and the load 93 might become 250 grams force (gf). While the flexiblepanel 20 was pressed with the oscillator tip portion 95, the oscillator94 was reciprocated with the load of 250 gf.

After 100,000 reciprocations, 200,000 reciprocations and 300,000reciprocations, the surface of the lower electrode layer 30 of the testpanel was observed, and evaluations were made such that one having noflaw observed at the surface of the lower electrode layer 30 was takenas a circle, one having a flaw partially observed was taken as atriangle, and one having a flaw observed over the entire slid portionwas taken as an X. Evaluation results are listed in Table 1 below.

TABLE 1 Composition of protective bodies, film forming method andresults of sliding tests Transparent Protective bodies Slidingcharacteristics conductive Film forming 100,000 200,000 300,000 filmComposition method reciprocations reciprocations reciprocationsComparative ITO — — X X X Example 1 Comparative ITO Nb Sputtering ◯ Δ XExample 2 Example 1 ITO Nb_(x)O_(y) Reactive sputtering ◯ ◯ Δ Example 2ITO Nb_(x)O_(y) Metha mode ◯ ◯ ◯ Example 3 ITO Nb_(x)O_(y) Ion gun ◯ ◯ ◯Example 4 ITO Nb/Nb_(x)O_(y) Reactive sputtering ◯ ◯ ◯ Example 5 ITONb/Nb_(x)O_(y)/ITO Reactive sputtering ◯ ◯ ◯ Example 6 ITO Ti_(x)O_(y)Ion gun ◯ ◯ ◯ Example 7 ITO Ti/Ti_(x)O_(y) Reactive sputtering ◯ ◯ ◯Example 8 ITO Ti/Ti_(x)N_(y) Reactive sputtering ◯ ◯ ◯ Example 9 ITOTi/Ti_(x)O_(y)N_(z) Reactive sputtering ◯ ◯ ◯ Example 10 ITOTi/Ti_(x)O_(y)/Si_(x)O_(y) Reactive sputtering ◯ ◯ ◯ Comparative AZO — —X X X Example 3 Example 11 AZO Nb/Nb_(x)O_(y) Reactive sputtering ◯ ◯ ◯Example 12 AZO Ti/Ti_(x)O_(y) Reactive sputtering ◯ ◯ ◯ ◯: No scratchseen, Δ: Scratches partially seen, X: Scratches seen over entire slidportion

As is clear from the above-described Table 1, it is confirmed thatabrasion resistance is high if a protecting film containing either oneor both of the metal oxide and the metal nitride is formed in at leastthe surface portions of the protective bodies 32.

<Surface States and Sliding Tests>

In the test pieces of the above-described Comparative Example 1, andExamples 1 and 6, the number of islands (protective bodies 32) in anobservation area of 950 nm×1270 nm (1.2 μm²) was counted. The number ofthe islands in the observation area and the number (density) obtained byconverting the number of the islands to a number per 1 μm² are listed inTable 2 below.

TABLE 2 Number of protective bodies (islands) and results of slidingtest Number Density Sliding characteristics of of islands 100,000200,000 300,000 islands [number/μm²] reciprocations reciprocationsreciprocations Comparative Example 1(a) 0 0 X X X Example 1(b) 4 3 ◯ ◯ ΔExample 1a(c) 37 31 ◯ ◯ ◯ Example 6(d) 176 147 ◯ ◯ ◯ Example 6a(e) 245204 ◯ ◯ ◯ Example 6b(f) 437 364 ◯ ◯ Δ ◯: No scratch seen, Δ: Scratchespartially seen, X: Scratches seen over entire slid portion

In addition, each of test pieces was prepared under the same conditionas in Examples 1 and 6 except that the film forming time was prolongedin order to increase the number of the islands. With respect to thesetest pieces, SEM photographs were taken under the same condition as inExamples 1 and 6.

FIGS. 15( a) to (f) are SEM photographs of the test pieces: FIG. 15( a)is Comparative Example 1; FIG. 15( b) is Example 1; FIG. 15( c) isExample 1a in which the film forming time of Example 1 was prolonged;FIG. 15( d) is Example 6; FIG. 15( e) is Example 6a in which the filmforming time of Example 6 was prolonged; and FIG. 15( f) is Example 6bin which the film forming time was further prolonged than in Example 6a.

The number of islands in each test piece was measured from the SEMphotograph under the same condition as in Comparative Example 1 andExamples 1 and 6, and the density of the islands was calculated. Inaddition, the above-described sliding characteristics tests were alsocarried out. Results thereof are listed in Table 2 above.

As is seen from Table 2 above, since the protective bodies 32 wereformed by the reactive sputtering in Example 1, the number of theislands is small, and the sliding characteristics are inferior as well.However, if the film forming time is prolonged, as in Example 1a, evenin the same reactive sputtering method as in Example 1, the number ofthe islands increases and the sliding characteristics are improved.

However, in Examples 6, 6a and 6b in which the metal atomic layer isfirst formed, the number of the islands is greater as compared withExamples 1 and 1a. Since the film forming speed is also slow in the caseof the reactive sputtering, it is understood that, in the presentinvention, the reaction in which the metal atomic layer is reacted withthe reactive gas is better than the reactive sputtering method in whicha layer of the reaction product between the metal and the reactive gasis formed from the beginning.

Example 1a and Examples 6, 6a and 6b have practically sufficient slidingcharacteristics. Since the sizes (diameters) of the islands in Exampleswere 100 Å or more to 600 Å or less (10 nm or more to 60 nm or less),the film forming time needs to be controlled so that the protectivebodies 32 having the diameters of 10 nm or more to 60 nm or less arepresent at a ratio of 3 or more to 364 or less per 1 μm², in order toobtain the practically sufficient sliding characteristics.

Meanwhile, when the reactive gas was plasmatized and the film formationwere carried out in the metal mode while the metal target 61 was beingsputtered in the above-described film forming apparatus 50, thesputtering speed almost did not change as compared with a case where themetal target 61 was sputtered without the introduction of the reactivegas. This shows that no reaction product is formed on the surface of themetal target 61 in the metal mode.

To the contrary, when sputtering was carried out in another reactivesputtering apparatus by feeding the sputtering gas and the O₂ gas into aspace between the Si target and an object to processed, the sputteringspeed was decreased to ⅓ as compared with a case where the sputteringwas carried out by feeding the sputtering gas alone. When the sputteringspeed is slow, the film forming speed becomes lower. Therefore, themethod, in which, after the metal atomic layer is formed, the metalatomic layer is reacted with the reactive gas, is the most efficient.

<Kinds of Metallic Materials>

Test pieces in Examples 13 to 15 were prepared under the same conditionas in Example 3 except that the constituent material of the metal target61 was changed from Nb to Zr, Ta or Si. SEM photographs were taken, andthe above-described “Sliding characteristics tests” were carried out.The SEM photographs of Examples 13 to 15 are shown in FIGS. 16 to 18,and results of the sliding characteristics tests are listed in Table 3below.

TABLE 3 Composition of protective bodies, film forming method, andresults of sliding test Transparent Protective bodies Slidingcharacteristics conductive Film forming 100,000 200,000 300,000 filmComposition method reciprocations reciprocations reciprocations Example13 ITO Zr/Zr_(x)O_(y) Ion gun ◯ ◯ ◯ Example 14 ITO Ta/Ta_(x)O_(y) Iongun ◯ ◯ ◯ Example 15 ITO Si/Si_(x)O_(y) Ion gun ◯ ◯ ◯ ◯: No scratchseen, Δ: Scratches partially seen, X: Scratches seen over entire slidportion

In Table 3 above, Zr_(x)O_(y) (x and y are actual numbers) is azirconium oxide such as ZrO₂ or the like, Ta_(x)O_(y) (x and y areactual numbers) is a tantalum oxide such as Ta₂O₅ or the like, andSi_(x)O_(y) (x and y are actual numbers) is a silicon oxide such as SiO₂or the like.

It was confirmed from FIGS. 13 to 16 that island-shaped protectivebodies were formed on the surface. In addition, it is seen that theresults of the sliding characteristics tests are good, and the abrasionresistances of the protective bodies were high, even if the metallicmaterial is replaced by Zr, Ta or Si.

What is claimed is:
 1. A touch panel in which first and second panelshave first and second substrates and first and second transparentelectrodes respectively disposed on the corresponding first and secondsubstrates, the first and second panels being separately arranged in astate such that faces having the first and second transparent electrodesdisposed thereon are facing toward each other, and the first and secondtransparent electrodes are brought into contact when either one or bothof the first and second panels are pressed, wherein the firsttransparent electrode comprises a transparent conductive film andprotective bodies which are formed in a piled-up manner on a surface ofthe transparent conductive film and scattered in a form of islands onthe surface of the transparent conductive film, wherein a protectingfilm, containing at least one of a nitride of a metallic material and anoxide of the metallic material, is exposed on surfaces of the protectivebodies.
 2. The touch panel according to claim 1, wherein the metallicmaterial comprises at least one kind of metal selected from a metalgroup consisting of Ti, Nb, Zr, Ta and Si, and the transparentconductive film has a lower resistance than the protecting film.
 3. Thetouch panel according to claim 1, wherein the first substrate is a resinfilm.
 4. The touch panel according to claim 1, wherein the secondsubstrate is a resin film.
 5. The touch panel according to claim 1,wherein a diameter of the protective body is at least 3 nm and at most100 nm.
 6. The touch panel according to claim 1, wherein a filmthickness of the protective body is less than 2.5 nm.